Random Data Generator

 Random Number Generator:

public String randomNumberGenerator(int length) throws Exception{
        Random random = new Random();
        char[] digits = new char[length];
        digits[0] = (char) (random.nextInt(9) + '1');
        for (int i = 1; i < length; i++) {
            digits[i] = (char) (random.nextInt(10) + '0');
        }
        long st = Long.parseLong(new String(digits));
        String uniqueID = String.valueOf(st);
        return uniqueID;
    } 

 Random String Generator:

public String randomStringGenerator(int length) throws Exception {
        // Chose a Character random from this String
        String AlphaNumericString = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "abcdefghijklmnopqrstuvxyz";

        // create StringBuffer size of AlphaNumericString
        StringBuilder sb = new StringBuilder(length);

        for (int i = 0; i < length; i++) {
            int index = (int) (AlphaNumericString.length() * Math.random());

            // add Character one by one in end of sb
            sb.append(AlphaNumericString.charAt(index));
        }

        return sb.toString();
    }

Random Alpha Numeric Generator:

public String randomAlphaNumericGenerator(int length) throws Exception {
        // chose a Character random from this String
        String AlphaNumericString = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "0123456789" + "abcdefghijklmnopqrstuvxyz";

        // create StringBuffer size of AlphaNumericString
        StringBuilder sb = new StringBuilder(length);

        for (int i = 0; i < length; i++) {
            int index = (int) (AlphaNumericString.length() * Math.random());

            // add Character one by one in end of sb
            sb.append(AlphaNumericString.charAt(index));
        }

        return sb.toString();
    }

Random Date Generator:

Enter Start and End Year.

public static int randomInBetween(int start, int end) {
        return start + (int) Math.round(Math.random() * (end - start));
    }

public String randomDateGenerator(int startYear, int endYear) throws Exception {
        int day = createRandomIntBetween(1, 28);
        int month = createRandomIntBetween(1, 12);
        int year = createRandomIntBetween(startYear, endYear);
        return LocalDate.of(year, month, day).toString();
    }

Calculate The Discount Price:

public String calculateDiscount(String Percentage, String Amount) {
        Amount= Amount.replace(",", "");                                                                                                                BigDecimal price = new BigDecimal(Amount);
        BigDecimal discount = new BigDecimal(Percentage);
        BigDecimal ONE_HUNDRED = new BigDecimal(100);
        BigDecimal discountValue = price.multiply(discount).divide(ONE_HUNDRED);
        discountValue = price.subtract(discountValue);
        discountValue = discountValue.setScale(2, BigDecimal.ROUND_HALF_UP);
        double value = Double.parseDouble(discountValue.toString());
        String afterDiscount = NumberFormat.getCurrencyInstance().format(value);
        // To remove prefix $ symbol
        afterDiscount = afterDiscount.substring(1);
        System.out.println("Amount after discount: " + afterDiscount);
        return afterDiscount;
    }